The songs are MP3"s and am playing them on Windows Media Player.

ok actually i need more info, but let me put it this way

1. then you try to play it, its absolute silence! not even a noise.
check to see the filesize is zero.

2. then you play it, its just full of noise, then it is corrupted!
the reason for corruption can be of two kinds, first you accepted the file inspite of verification error, secondly there are certian intrests out there trying to destroy downloads, simply by putting carbage for download. If it is the last, then try to download those files again, but! select file that have different filesizes or even bitrates if shown.